McNeill on Civilize Societies’ disease advantage

William McNeill wrote Plagues and People in 1976. In 1998 it was reprinted with the addition of his analysis of the AIDs disease. He thought the earlier publication was valid as is. I am 22% through the Kindle edition and have run across only one strange comment about the effect of disease upon the Aztecs during the Spanish invasion. His comment was something like one I made recently in regard to something else, namely that he read it some place but couldn’t remember where but (and here he expressed more confidence in his memory than I did in mine) some (primary or nearly primary) source provided evidence that disease was Cortes’s most potent ally. Yes, a few of the local Amerindian tribes (who had been mistreated by the Aztecs) helped Cortes, but only after they were convinced he was going to win. He had to demonstrate to them that he could win without them, and they wanted to be on the winning side.

What follows is McNeill more broadly (and more usefully) writing about the process whereby disease assists a Civilized Society against a more primitive one. This passage would seem to apply to Rome’s ability to conquer with regularity (at least early on), all the nearby more-numerous but also more-primitive tribes.

“When civilized societies learned to live with the “childhood diseases” that can only persist among large human populations, they acquired a very potent biological weapon. It came into play whenever new contacts with previously isolated, smaller human groups occurred. Civilized diseases when let loose among a population that lacked any prior exposure to the germ in question quickly assumed drastic proportions, killing off old and young alike instead of remaining a perhaps serious, but still tolerable, disease affecting small children.

“The disruptive effect of such an epidemic is likely to be greater than the mere loss of life, severe as that may be. Often survivors are demoralized, and lose all faith in inherited custom and belief which had not prepared them for such a disaster. Sometimes new infections actually manifest their greatest virulence among young adults, owing, some doctors believe, to excessive vigor of this age-group’s antibody reactions to the invading disease organism. Population losses within the twenty-to-forty age bracket are obviously far more damaging to society at large than comparably numerous destruction of either the very young or the very old. Indeed, any community that loses a substantial percentage of its young adults in a single epidemic finds it hard to maintain itself materially and spiritually. When an initial exposure to one civilized infection is swiftly followed by similarly destructive exposure to others, the structural cohesion of the community is almost certain to collapse. In the early millennia of civilized history, the result was sporadically to create a fringe of half-empty land on the margins of civilized societies. Simple folk brought into contact with urban populations always risked demoralizing and destructive disease encounters. Survivors were often in no position to offer serious resistance to thoroughgoing incorporation into the civilized body politic.

“To be sure, warfare characteristically mingled with and masked this epidemiological process. Trade, which was imperfectly distinct from warlike raiding, was another normal way for civilized folk to probe new lands. And since war and trade relations have often entered civilized records, whereas epidemics among illiterate and helpless border folk have not . . .” [McNeil, William. Plagues and Peoples (p. 86-87). Knopf Doubleday Publishing Group. Kindle Edition.]